392 SAND 



and slate; even the Table Mountain sandstone of the 

 west coast, Clanwilliam and Van Ehyn's Dorp, is in 

 places covered with a ferruginous cemented material 

 grading on the one hand into the raised beaches of that 

 coast and on the other into the surface quartzites. 

 Near Strand Fontein, a few miles south of the Olifant's 

 Kiver mouth, the almost flow-like appearance of the 

 remains of the dark limonitic quartzite lying on the 

 Table Mountain sandstone and filling up the open joints 

 at various levels from that of the high tide to 200 feet 

 above it has given rise to the idea amongst the people in 

 the neighbourhood that it is lava. This somewhat re- 

 markable variety of the lateritic rocks is certainly due to 

 the deposition of the hydrated iron oxide, leached out 

 from the underlying sandstones, between the sand grains 

 which reached their present position through the agencies 

 of wind and water. 



5. SAND. 



Extensive areas in various parts of the Colony are 

 covered to a more or less considerable depth by sand. 

 These deposits of sand may be roughly divided into two 

 groups ; those formed inland and those near the coast. 



The inland sands are chiefly developed in the north 

 and north-west. The largest area is in Gordonia and 

 Bechuan aland, the southern end of the great sandy 

 country called the Kalahari. Thousands of square 

 miles are deeply covered with reddish or yellowish sand 

 largely made up of quartz grains with a small quantity 

 of felspar and other minerals. The red colour is due to 

 a thin coating of oxide of iron, which disappears when 



